Neuropsychological Outcome after Epilepsy Surgery in Pediatric Patients / 대한소아신경학회지

PURPOSE: With this study, we evaluated the operative and neuropsychological outcomes after epilepsy surgery in children. METHODS: We studied the surgical outcomes and the possibly related factors retrospectively by reviewing the medical records of 28 patients who underwent epilepsy surgery before the age of 15 years along with the battery of neuropsychological tests. RESULTS: The mean age of seizure onset was 84.8 months, and the mean period at the surgery after the onset of seizure was 62.4 months. Among 28 patients, 15 had complex partial seizures(CPS) only, 11 CPS with secondary generalization, and two simple partial seizures in addition to CPS. The types of the surgery included anterior temporal lobectomy with amygdalo-hippocampectomy(9 patients), extra-temporal or lateral temporal resection with temporal lobectomy(16 patients), and extra-temporal resection(3 patients). Evaluating their surgical outcomes, 21 patients belonged to Engel class I, five to class II, and each one to class III and IV respectively. There was no significant difference in full scale intelligence quotient(IQ) and verbal IQ after the epilepsy surgery. However, the performance IQ was higher in the older age group after the operation(P=0.011). When the patients were divided into two prognostic groups, the Engel classification after the surgery was the only significant influencing factor(P=0.037). CONCLUSION: The intelligence quotient and memory did not deteriorate after the epilepsy surgery. The overall neuropsychological outcomes improved in about half of the patients. And it was significantly influenced by the seizure outcomes after the surgery.

Retrograde Amnesia Following Anterior Thalamic Infarction

BACKGROUND: Retrograde amnesia (RA) refers to the failure to recall events that occurred before a brain injury. RA is known to be associated with brain lesions involving the hippocampus, entorhinal cortex and the frontal lobe. Anterior thalamic lesion often causes anterograde amnesia but rarely causes RA. The aim of the present study is in two parts . First, we discuss the neuroanatomical perspectives of RA based on our case with severe RA after a right anterior thalamic infarction. Second, we introduce a test for RA termed the "Korean Public Events Recall Test (K-PERT)", which was developed based on famous Korean public events from 1966 to 1997. METHODS: A 62-year-old woman with transient RA after a left anterior thalamic infarction 4 years ago presented severe and persistent RA following a right anterior thalamic infarction. We followed up the patient with neuropsychological tests. We also performed the K-PERT on the patient as well as on 14 women of the same age and education. RESULTS: Neuropsychological tests showed severe impairment in autobiographical memory with frontal lobe dysfunction. On K-PERT, the normal controls scored 13.7 +/- 3.7 in recall and 21.2 +/- 3.1 in recognition out of a maximum score of 30, whereas the patient obtained only 3/30 and 4/30, respectively. CONCLUSIONS: In our case, RA might have resulted from damage to the pathway that retrieves old memories, which are stored in the frontal lobe. Thus, anterior thalamus might be viewed as the gate of memory engram. Further studies are needed to elaborate the usefulness of K-PERT as an objective tool for investigating remote memory.

Globus Pallidus Lesions Associated with High Mountain Climbing

Acute mountain sickness (AMS) occurs commonly in hikers who are rapidly exposed to high altitude environments. Despite the numerous reports of AMS, few studies have reported pallidal lesions associated with altitude sickness. A previously healthy 49-yr-old Korean patient, after ascent to 4,700 m, suffered symptoms consistent with AMS. After returning home, the patient showed changes in personality characterized by abulia, indifference, and indecisiveness. T2 weighted brain magnetic resonance imaging showed high signal lesions involving bilateral globus pallidus. Our case suggests that globus pallidus injury should be included in the differential diagnosis of patients with personality or cognitive change after recovery from AMS.

Primary Progressive Amnesia 3 Cases: a Case Study

BACKGROUND: Isolated amnesia without dementia results from various etiologies. When caused by degenerative etiol-ogy, it is recognized as a subtype of Alzheimer's disease (AD) and was termed progressive isolated amnesia or primary progressive amnesia (PPAm). Patients with PPAm have rarely been reported. We describe neuropsychogical and neu-roimaging findings in 3 patients with PPAm. METHODS: Patient 1 (M/74) showed progressive amnesia for 8 years and then developed probable AD. Patient 2 (M/76) and 3 (F/69) showed severe progressive amnesia without dementia for 9 years. Neuropsycholgical evaluations were conducted 3 times in each patient at 1 to 4 year interval. Hippocampal vol-ume was measured by a manual tracing in 1.6 mm thick coronal MRI slices which was obtained perpendicular to the long axis of the hippocampus. RESULTS: Neuropsychological tests revealed verbal and nonverbal memory loss with preservation of attention, language, praxis, visuospatial and frontal-executive functions. Right and left hippocampal vol-umes for patient 1, 2 and 3 were 1580.46/1586.38, 682.96/609 and 1152.84/1272.50 mm3 respectively, a result indica-tive of severe hippocampal atrophy. CONCLUSIONS: Neuropsychological profiles and clinical course of our patients fur-ther support the view that PPAm results from degenerative etiology. Severe atrophy of the hippocampus with relative preservation of other association cortices suggest that PPAm may be another focal cortical atrophy syndrome involving medial temporal region.

Neuropsychological and Neuroimaging Findings of Semantic Dementia

BACKGROUND: Semantic dementia (SD) is a temporal variant of frontotemporal lobar degeneration (FTLD), which is characterized by naming difficulty, decreased comprehension of words, prosopagnosia and object visual agnosia. We report clinical features, neuropsychological and neuroimaging findings of 4 patients with SD. METHODS: Of 55 patients diagnosed as having FTLD between Jan 1995 and May 2001 at Samsung Medical Center, four patients fulfilled the diagnostic criteria of SD proposed by consensus on FTLD diagnostic criteria. We investigated their clinical features such as presenting symptoms and abnormal behaviors, neuropsychological and neuroimaging findings. Neuropsychological tests included the Seoul Neuropsychological Screening Battery, the Korean-version of Western Aphasia Battery and Hanja reading and writing. All patients underwent brain MRI and FDG-PET. RESULTS: All of the patients showed naming difficulty as a presenting symptom. Language assessments showed severe naming and compre-hension difficulties with preserved fluency and repetition, which were compatible with transcortical sensory aphasia. Whereas Hangul reading aloud and writing were intact, three patients were impaired at Hanja reading and writing. Other neuropsychological tests were remarkable for prosopagnosia, object visual agnosia and memory loss. Brain MRI showed asymmetric temporal atrophies, mainly left antero-inferior temporal cortices. FDG-PET also showed hypome-tabolism in bilateral anterior temporal lobes, more severe on the left. CONCLUSIONS: Our SD patients had characteristic neuropsychological and neuroimaging findings, which can be differentiated from other neurodegenerative diseases. We also found Hanja alexia and agraphia in SD patients, which has not been reported yet.

Is Brain Biopsy Rational in Shunt Operation of Normal Pressure Hydrocephalus in Elderly?

Early detection of AD in its initial or preclinical stage has become increasingly important. We report a 73-year-old woman who was confirmed to have AD by a cortical biopsy performed concomitantly during a shunt operation for hydrocephalus. The triads of hydrocephalus improved after the operation, as did follow-up neuropsychological and FDG-PET findings. However, 2.5 years after the operation, the patient developed cognitive declines with abnormal behaviors, which was considered to be an evolved form of AD from the preclinical stage.